Describe the current beliefs as to why people age

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Deserts (especially true deserts) are not easy places for animals to live. animals who live in them often have special features that them survive. which adaptation would be for this group of animals? a) keen eye sight b) short, narrow legs c) tolerate heat d) webbed feet

In the 1500s, an astronomer developed a new model of the universe. this model had the sun at the center of the universe, not earth. who was this astronomer?